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There is a very interesting Youtube Video British Plugs Are Better Than All Other Plugs, And Here's Why that indicates some engineering reasons why the British power plug is safer than for example the American style power plug.

As you can see in the video there are a variety of features that ought to make the British plugs safer than American and other plugs, including:

  • the powered slots are shuttered until opened by a third safety-pin
  • the pins are covered partway down by an insulator so you cannot touch the metal pins when they are connected
  • the plug has an independent fuse
  • the internal wires are colour-labeled "bLue" for Left and "bRown" for Right
  • the grounding wire is longer than the powered wires (so if the cable is yanked out the ground should be the last thing to disconnect)
  • The distance from pins to edge of plug is large to reduce risk of fingers getting near pins.
  • The cable exits at 90 degrees so that pulling the cable is less likely to pull the plug partially out.
  • The ground pin is longer so last to unplug.
  • It is part of a system that has switches on outlets so that appliances can be turned off at the wall (rather than leaving unplugged plugs lying on the floor).
  • The fuse is located so you have to unplug before changing.
  • cables are clamped by a cord-grip

Do these interesting and seemingly important engineering feats bear out in reality? Has anyone any got any statistics on the number of deaths and injuries from electrical plugs in Britain, and compared them to other areas that do not have these safety features in their power plugs?

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    Given that US power is 110/120V and UK power is 220/240 safety measures are going to be harder to compare. – Alan Munn Jul 28 '14 at 22:36
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    @AlanMunn: The US may not be the best comparison to mention, but there's lots of the world to compare to at 220V, with few of those places having the protections of the UK-style plug. In any case, won't the higher voltage in the UK vs in the US lead to more likely arcing in the UK - arguably making it more dangerous than in the US. If that is the case if the stats show lower electricity injuries/deaths in the UK it would be in spite of the higher voltage? – Brian M. Hunt Jul 28 '14 at 23:38
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  • I recall the Thai plug being identical to the American plug, but was warned that they were on 220, so you still need a converter. A safety analysis that wants to compare these plug types while isolating for current differences would probably want to use the Thai standard. – fredsbend Aug 4 at 21:03
  • Anecdote: a US colleague told me he had found burn marks on the carpet underneath an electric outlet. Turns out his son and friend had been creating sparks by shorting the pins with a knife, and accidentally melted the knife. Not possible with a UK plug. – Paul Johnson Aug 5 at 7:22
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Summary

Death rates for cause electric accidents (per million inhabitants and year) do not differ significantly between Ireland (UK type G) and Germany (Schuko), see below (I did not find similar statistics for the UK, nor sufficient detail to break the numbers down to plug/socket vs. other causes of electric accidents).


There are at least two safety features encountered in continental European plug/socket norms that UK type G does not have: added mechanical safety of a deeply inset socket and plugs that do not tend to fall pins upside (and if they do, they have rounded pins).

Both features could be achieved quite easily for UK plugs, so I'd say it is therefore not the best/safest of all possible plug systems.

In terms of actually existing plug systems, Swiss type J is the hot candidate, with e.g. French type E and Schuko/type F being important competitors. Whether you accept them as as good or even better depends largely on whether

  • safety features that are available but not universally mandatory count as existing or not, and
  • lack of safety features that are relevant only for UK-style ring circuits counts against a plug/socket system that is used in radial-circuit-only countries. And other similar post-war decisions (switches belong to socket vs. switches belong to device)

TL DR

Type E (plug types) French or "French Schuko" (they can be combined in one plug) or e.g. Swiss T13/type J are available with all the safety functions OP lists for the UK system except the extra fuse which is necessary for the UK-type ring circuits, but would be without function for the continental European purely radial installations. German Schuko (type F) lacks the feature of having defined positions for zero and phase but by that offers the advantage of choice between two plugging directions - which also has a safety advantage, but a different one. list with shorter descriptions but in English.

There is also type N (an international norm much younger than the other 4 plug/socket types) which is quite similar to the Swiss system and which tries to combine all those advantages (except the two plugging directions) - but it is not in widespread use, so I won't discuss it.

They (incl. Schuko) have the additional safety-relevant feature compared to the UK system that the sockets are inset. And this feature makes the statement in the video at 1:15 that European plugs expose the hot pin to fingers when half plugged in wrong for the vast majority of continental European plugs/sockets (old pins and sockets that do have this danger are probably still occasionally to be encountered in some places, though [have a close look at granddad's workshop]. But Wikipedia shows not only old Swiss plugs but also before-type-G UK plug pictures). For Schuko this statement was wrong already 20 years before type G plugs were invented (the Swiss J is a few years younger than UK type G, French E I don't know).

Some of the features (switches at the outlet) are not mandatory, for some it varies by country whether and where they are mandatory (e.g. shuttering) or whether they are actually used (polarity). (But then I also don't know whether all countries that use UK G-type plugs prescribe the all same safety features)


Point by point comparison

As others have said, it doesn't make sense to discuss plug safety without looking at general installation principles such as ring vs. radial circuits, the design of the socket into which the plug goes etc.

the powered slots are shuttered until opened by a third safety-pin

French E, Schuko F and Swiss J plugs are available with internal shutters.

The Schuko internal shutters open if pins are pushed into both zero and phase at the same time. So the European baby needs two screwdrivers to put into zero and phase, whereas the UK baby needs two screwdrivers to put into ground and phase. The European baby with parents that use a lock cap (see below at end) will not be able to participate in this early education engineering competition.

According to Wikipedia, such shutters are required by law in several countries (e.g. Scandinavian countries, Portugal). Some other countries have varying requirements depending on where the socket is, e.g. German kindergardens have to have shuttered Schuko (whereas offices or industrial workshops don't) but this is prescribed by the mandatory accident insurance's building regulations rather than by the electrical norm for sockets.
The inset sockets allow using "child safety caps" that are plugged into the socket to close it. They have been in use at least since the 70s in Germany, and according to Wikipedia there were even ceramic shutters before plastic plugs became available)

the pins are covered partway down by an insulator so you cannot touch the metal pins when they are connected

Those European systems mostly use the deep inset instead. The effect is the same: you cannot touch the metal pins while there is a connection. The Swiss type J plug/socket uses both: plastic sleeve and inset (the Swiss had sockets without inset before, and they may still be around).

the plug has an independent fuse

No for the continental varieties, but: the UK fuse at the outlet is necessary only due to the ring circuit installation. French/Swiss/Schuko are used with radial installation where each outlet has the same rating as the radial circuit, so a second fuse of "one size fits all type" at the plug would not add any safety to the one in the fuse box.

Many devices have their own fuse, which may be for smaller current, thermo fuse, ... (whatever is needed for added safety). The UK plug fuse is not a replacement for such a device fuse (As I understand, the plug fuses are typically one-size-fits-all 13 A fuses. And in any case they are supposed to be replaced by the end user and there is nothing to keep that end user from replacing a 3 A fuse by a 13 A one.)

Also in continental European devices, the physical size of fuses is the same for various current and time ratings. However, replacing these for many devices requires at least some determination ("special" screws etc.) which is meant to make one think whether one is actually able to decide what should be done here.

the internal wires are colour-labeled "bLue" for Left and "bRown" for Right

The saying about left and right is really a memory aid, not a safety feature. Blue = neutral and brown (or black) = phase (live, hot) is the same in continental Europe.

Swiss and French plugs do in principle have a direction ("polarity") like the UK plugs, whereas Schuko does not (because the 220 V AC were between 2 phases when it was developed about 20 years before the UK system). Which also meant that switches needed to disconnect both lines. Nowadays Germany also has the 220 V between neutral and phase, but appliances must be safe to plug in both ways. But AFAIK the French norm does not specify mandatory positions for zero and phase, and I'm not sure about Switzerland, neither. For the French, since most plugs are actually French + Schuko plugs, the devices anyways cannot rely on position. Some countries have conventions on zero/phase position, though.

OTOH, Schuko has the advantage that the plug can be used in two directions.

In terms of safety,

  • polarity and switch requirements are something that needs to be considered together: polarity and phase switched is OK, and so is unpolar and both live wires switched.
  • Zero anyways becomes live as soon as the device is switched on, so any safety consideration that really looks at live wire safety needs to be applied to zero as well.
  • Nevertheless, knowing which side the phase is may still add some safety
  • One may still prescribe disconnecting both phase and zero to guard against faults that make the zero live for polar systems as in the UK.
  • having 2 positions to plug in may add mechanical safety with 90° angled plugs (i.e. lower risk of damaging the cable/plug by "foreseeable misuse" of the cable taking a sharp 180° turn).
    180° turns are less frequent with straight plugs. I don't know for sure, but I've never seen a Swiss type J angled plug - so they may have decided to not have 90° plugs for safety reasons...

the grounding wire is longer than the powered wires (so if the cable is yanked out the ground should be the last thing to disconnect)

This is good installation practice (also outside the UK), and the plug construction allows this, but I did not see anything that ensures this will be the case in the UK plug in the video: if someone installs the ground really tightly, it will disconnect earlier. In contrast, I've seen devices where the ground wire was laid around some comparably flimsy plastic pins. That design actually (almost) ensures or at least encourages that the ground wire will be longer (when the cable is yanked through the strain relief, the pins may break) and before they break it adds additional friction like a somewhat stronger strain relief on the ground wire.

However, I learned the same for wiring Schuko plugs (not in school, though). Don't know for J type, but French and Schuko tend to be the same on the plug side nowadays, so I imagine the same is true for the French plugs.

The distance from pins to edge of plug is large to reduce risk of fingers getting near pins.

The deeply inset sockets make sure the fingers cannot be at the socket facing side when the plug connects.

Size of Schuko and French plugs is discussed as unnecessarily big nowadays (it was needed in the past before the development of the tough (strong but not brittle, slightly elastic) plastics that are used nowadays). The Swiss system can have 3 sockets in a slot for 1 Schuko or French socket.

The cable exits at 90 degrees so that pulling the cable is less likely to pull the plug partially out.

The deeply inset socket designs do not allow unplugging in any direction but straight out, regardless of whether an angled or straight plug is used (both exist). The Swiss and Schuko systems in addition have mechanical guards against twisting that are independent of the electrical pins.

Pulling force (yanking) at a cable is often worse with a 90° plug than with a straight plug (due to the direction usually being into the room, i.e. at an angle compared to the end of the plug) in terms of the risk of damaging the cable/plug.

Not sure whether prescribing 90° plugs is really a safety feature in the end - but 90° plugs are considered OK in terms of safety also in continental Europe.

The ground pin is longer so last to unplug.

French/Swiss/Schuko also connect ground first. The pin doesn't need to be longer for that, e.g. the Swiss system has the connection springs for the neutral and phase deeper inset than the ground one.

The Schuko type ground contacts are easier to bend than varieties with more sturdy pins (though with seriously bent ground contacts one won't be able to put a plug into the socket), and there is a certain risk that they may be coated e.g. with wall paint when painting (though they are springs and would usually automatically scratch off something like wall paint). The French system with a big pin sticking out in the middle is again less prone to that, and the Swiss system entirely avoids the risk.

It is part of a system that has switches on outlets so that appliances can be turned off at the wall (rather than leaving unplugged plugs lying on the floor).

I'm not aware of switches at each outlet being mandatory in any French system or Schuko country, nor in Switzerland. You can get switchable sockets if you like, though. Or "adapters" (for lack of a better word) with all kinds of switches: simple mechanical, IoT switches, time switches, ...

I like the idea as a convenient feature (and I like even more if devices have switches that properly turn them off), but I'm not so sure about added safety:

  • unplugging is still more safe in terms of being really sure that the device is disconnected.
  • when unplugged, the whole cable & plug should be stowed. This not only prevents stepping on the plug (which depending on the location we talk about is a non-issue) but also tripping over the cable.
  • adding a switch that is not needed is another thing that may break. It may be safer to prescripe switches that properly disconnect for all devices, also since a broken switch is easer to repair in a device that can be brought to an electrical shop.

The fuse is located so you have to unplug before changing.

see above - non issue since that fuse is not necessary.

cables are clamped by a cord-grip

Strain relief is also mandatory in Germany (Schuko), and I cannot imagine France or Switzerland not having mandatory strain relief, neither (though properly speaking I don't know it for other countries).


Safety feature UK type G plug/socket doesn't have:

  • Inset sockets protect the plugged in plug mechanically, e.g. twisting forces do not go on the electrical pins (not for French E), the shape of the plug takes care of them and allows to enter/remove only straight (Schuko, Swiss T13/J). This also makes accidentally yanking out (the intact plug) more unlikely.

    (There are also mechanically even more connected versions, e.g. Schuko with bayonet coupling which may even be waterproof against short-time immersion, but I assume the question is for plug types used in households.)

    The inset construction also allows removable caps instead of shutters for child protection or to lock a socket.

    It acts as "finger safety" device as well, though that property can be achieved also by having the contacts deeper below the surface of a flat socket and an insulating sleeve (as in UK plugs).

  • Stepping on plugs: the 3 continental plug types fall onto their side, and their pins are rounded rather than having the still comparably sharp though beveled edges of pins of the UK plugs.


Statistics

I found statistics about electricity-related deaths published by German VDE (Schuko) and the Irish Health and Safety Authority ("UK" plug), but not for UK. The VDE statistic specifies that they look at ICD-10 causes of mortality W85 - W87, i.e. the deaths exclude suicides by electricity, lightning strokes and railway electrical accidents. However, those exclusiond are also not relevant for this question.

  • In both countries, the rate of deadly accidents with electricity has been falling.

  • During the time window available for both countries (2000 - 2018), Ireland records a total of 49 deaths, Germany 1013. Ignoring the trend, we get:

                                              | IRL         | DE
    ------------------------------------------+-------------+------------
    number of deaths                          |          49 |        1013
    inhabitants                               |    4.13 mio |      82 mio
    death rate per (year * 1 mio inhabitants) |     0.62    |     0.65
       95 % conf. int. (by R, poisson.test()) | 0.45 - 0.83 | 0.61 - 0.69 
    

    Due to Ireland being much smaller than Germany, the estimated rate is much more uncertain: the complete 95 % confidence interval for Germany lies within the 95 % confidence interval for Ireland.

    A one-sided Poisson test (with the alternative hypothesis that the death rate in Germany is greater than in Ireland yields a p-value of 0.43, so we're far from a significant difference.

    The ratio death rate in Ireland / death rate in Germany is 0.96, with a two-sided 95 % confidence interval of 0.71 - 1.28. The death rate due to electrical accidents in Ireland thus may be said to be very roughly within ± 30% of the German rate.

  • Also, the German federal statistical office published detailed data on cause of death (Tiefgegliederte Todesursachen) which gives more detailed subgroups of cause of death, but they are not so detailed as to say whether the deaths are connected with plug/socket-related issues.

  • The Irish statistics have a table of case summaries, in which one death is listed that should have been prevented by the safety features discussed: a toddler "successfully" putting a nail into a socket.
    I did not find similarly detailed statistics or descriptions for Germany (only detailed statistics/descriptions for workplace electrical accidents)

  • Relevant for this question but not included in the above statistics are deaths by fires caused by faulty plug/socket. Irish Fatalities for Fire statistics give categories of suspected cause, including "Electrical Wiring" and "Electrical Appliance". A quick glance says that these causes are not rare, but I do not have time to dig into this.
    Again, I did not find German statistics on the cause of fatal fires, but about one third of the fires 2002 - 2019 had an electrical cause.

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    On the last point, while UK plugs do tend to fall with pins pointing up, the pins ends are bevelled rather than sharp corners, so you can't cut or scratch yourself. Stepping on one barefoot is still an unpleasant experience though. – Paul Johnson Aug 5 at 7:27
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    @PaulJohnson: I should have been more precise - I know they are beveled, but I also remember encountering some with "scratchy" edges (may have been badly manufactured). Stepping on the continental "bulky" continental varieties like Schuko or French plug isn't exactly nice, either. I'd say start stepping on them with one degree earler of your Fakir's certificate than the UK ones (or two: the stray lego degree is probably in between - and that's certainly a widely accepted risk)... – cbeleites unhappy with SX Aug 5 at 11:12
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    This is an answer based purely on a theoretical model. We expect answers to be based on empirical evidence rather than speculative predictions. It doesn't matter what the designers think should be safe. Which turns out to be empirically safer? – Oddthinking Aug 5 at 12:13
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Has anyone any got any statistics on the number of deaths and injuries from electrical plugs in Britain, and compared them to other areas that do not have these safety features in their power plugs?

Probably not, many have looked for such data without success.

The International Classification of Diseases (ICD) is often used to record causes of death. This has some codes for electrocution but they do not distinguish deaths due to design of plug or outlet from deaths due to faults in cables or equipment for example.

Are British plugs safer than all other plugs?

You cannot look at plugs in isolation, they are part of a system. In particular, BS1363 plugs are designed for use in UK electrical installations with wall-sockets that also meet compatible standards and are specifically designed for use with ring-mains circuits - which are standard in the UK but not used in almost all other countries.

British plugs do seem to have a greater number of safety features compared to other national standards of similar age (e.g. US plugs). In the absence of reliable and properly comparable statistics, any assessment of their actual relative safety must be a matter of subjective opinion or a theoretical engineering assessment.


References

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  • Yes, exactly. :o) I mean, the more I look at it the more I think it is an marvel of engineering and forethought. I just wonder whether it has made a significant difference in a statistical/actuarial sense. – Brian M. Hunt Jul 29 '14 at 12:19
  • Note that the fuse is useless as a life saving safety (it lets a few amps go through before melting, more than enough for killing a human). – Sklivvz Jul 29 '14 at 18:10
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    @Skliwz: Your life is still at risk from the appliance cable overheating and setting fire to your house while you and your family are asleep. Electrocution isn't the only electrical hazard BS1363 designers were concerned about. – RedGrittyBrick Jul 30 '14 at 9:00
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    @RedGrittyBrick agreed. I should have prefixed my comment with "contrary to popular belief..." – Sklivvz Jul 30 '14 at 16:30
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    Note that due to the possibility of a break in the ring getting unnoticed, it is claimed that there is a much higher fire risk for ring-mains installations, so I would say the whole system must be compared (possibly including things like voltage too) – PlasmaHH Jul 31 '14 at 14:26

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